Bioassay on the Allelopathy of Teak (Tectona grandis) and Its Effects on the Plant Communities of Teak Plantation in Taiwan

• Main Authors: Ching-Ju Lee, 李靜茹
• Other Authors: Fu-Yuan Lu
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/a5d83e

碩士 === 國立嘉義大學 === 森林暨自然資源學系研究所 === 96 === In the studies series of aqueous extracts of Tectona grandis were extracted from its root, stem, leaf and fallen leaves.The germination inhibition activities were assayed by treating the seeds of Brassica chinensis, Mikania micrantha, Bidens pilosa var. minor, Koelreuteria formosana and Alnus formosana with different concentrations of extracts, respectively.The results revealed that the effects of germination inhibition of extracts from different parts of Tectona grandis on Brassica chinensis, Mikania micrantha, Bidens pilosa var. minor increased as the concentrations of extracts increased, and the bioassay results exhibited a significant suppression of their radicle growth. The 1%、2% of extracts had promotion on seed germination and radicle growth of Koelreuteria formosana, but the 4% of extract had significant effect on root growth. Tectona grandis had an allelopathic phenomenon which can inhibition on seed germination of Brassica chinensis, Mikania micrantha, Bidens pilosa var. minor. A detail research on the community structure and species diversity of common teak（Tectona grandis） plantation and its adjacent secondary growths in low elevation of South Taiwan was carried out to survey and explore some problems about vegetation ecology. Total of 186 species, 156 genera and 67 families were recorded in these plots. Three main vegetation types were recognized by the Matrix Cluster Analysis as : 1. Tectona grandis-Dimocarpus longan type, 2. Ficus fistulosa - Ficus irisana type and 3. Macaranga tanarius-Dimocarpus longan type. Floor vegetation types have been recognized as 1. Arenga tremula -Dimocarpus longan type 2. Murdannia keisak-Passiflora suberosa L. type 3. Alpinia zerumbet- Lygodium japonicum type 4. Alocasia odora- Liriope spicata type. Tolerant trees i.e., Moraceae species, the dominant species in the vegetation communities will replace the intolerant species as succession proceeds.The pattern of DBH distribution of Common Teak plantation is in double bell-type, but Macaranga tanarius、Dimocarpus longan plantion is in contrary J-type, it showed that the Macaranga tanarius、Dimocarpus longan will take the dominant role of crown level during the successional stage in the future. There are evident differences in plant compositions between teak plantations and its adjacent secondary growths. It revealed that allelopathic effects of teak trees on the plant communities were very effective and evident.